In a refrigerating machine such as cold storages and air conditioners, a refrigerating machine oil is used with a refrigerant, in order to prevent friction, wear, and seizure in a compression sliding portion. Examples of the properties required for such refrigerating machine oils include compatibility with a refrigerant and compatibility with members inside the refrigerating machine.
That is, in addition to lubricity, thermal/chemical stability, and refrigerant compatibility in the presence of a refrigerant, the refrigerating machine oil is required not to degrade the members when coming in contact with the members of a refrigerating machine, and so on. Thus, depending on the material of the members in the refrigerating machine, it is suggested to use a refrigerating machine oil which is compatible with them. For example, in the following Patent Literature 1, a refrigerating machine oil for suppressing degradation of polyamide resin such as nylon is disclosed.